The proposed research will continue to study molds isolated from cheese for potential toxicity. Attempts will be made to characterize the specific toxic substances being produced. The isolated molds will be identified to the series and species level where possible. Additional food products including other cheeses, cured and processed meats, and refrigerated dough products will be examined for mold content. Molds that are found will be isolated and screened for toxicity using chicken embryos, rabbit skin sensitivity, Bacillus megaterium assay and chemical assays. Methods for extraction and analysis of patulin, penicillic acid and aflatoxins from cheese, meats and dough products will be refined and improved. Using these techniques, studies will be initiated concerning the conditions governing mold growth and production of patulin, penicillic acid and aflatoxins at low temperatures, in pure and mixed cultures on laboratory media and foods, including cheeses, meats and dough products. These studies will be done using known toxin producing molds obtained from various sources and carried in stock cultures. The studies will also involve molds isolated from the foods in question and proven to be toxic.